Can´t set featured image, library doesn´t loads

Hi! I´m experimenting a weird issue since I got suspended on my server for “abusing resources”. Now they tell me it isn´t related with them.

The thing is when I try to set a featured image or add images from the library within the post editing box, the modal box opens but images of the library doesn´t load.

I tried another browsers, disabling extensions, clearing the cache and contacting my server but still can´t use my wp properly